<template>
    <div class="child">
        <h3>我是Child组件</h3>
        {{sum}}
    </div>
</template>

<script lang="ts">
    import {ref} from 'vue'
    export default {
        async setup(){
            let sum = ref(0)
            let p = new Promise((resolve,reject) => {
                setTimeout(() => {
                    resolve({sum})
                },3000)
            })
            return await p
        }
    }
</script>

<style scoped lang="less">

</style>
